I have had clinical depression, although it wasn't so bad as to be disabling. You may very well say, "Then you did not have CD" Perhaps not. It related to my PD and would be classed as endogenous. CD of the exogenous variety is endemic in my wife's family. Her mother, brother, and one, possibly two of her sisters, two of four nieces, one of three nephews and our daughter are all subject to CD. My wife, Esther, has bouts of CD. With CD manifesting itself in families, one wonders if it might be a learned behaviour I believe that CD is caused by standards for an individual being set too high, whether by the individual or some external source, to possibly attain. When the standards are not met, the individual is subjected to criticism and ridicule, either self-imposed or externally, leading to feelings of inadequacy, self revulsion which grow exponentially and synergistically to include all aspects of performance, not just the area centred out for criticism. The road back is long and treacherous, because no one likes to admit being a failure, either in their own eyes or those of others. Robert Browning's aphorism "Your reach should exceed your grasp, else what's a heaven for" and many others like it encapsulate the primacy of ambition and success in society today. An individual with CD often has to scale back his standards and goals to ones which are realistically attainable. This can be particularly difficult if the standards have been implicit and relative rather than explicit and absolute. This is where professional help is necessary to guide the afflicted on a safe route.